Surgical instrument with separate tool head and method of use

ABSTRACT

Surgical instruments are disclosed in which an elongated shaft is used in conjunction with a separate, remotely actuable tool head for performing a procedure on a target tissue. The shaft has a tool engagement member carried at its distal end that is remotely actuable through the shaft to engage and release the tool head.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional PatentApplication Ser. No. 60/909,666, filed Apr. 2, 2007, which isincorporated herein by reference.

BACKGROUND

The present application is related to surgical instruments and, morespecifically but not exclusively, to robotic surgery instruments andmethods for their use. Specifically, the present application relates tothe provision of a plurality of specially configured tool heads for usewith a control arm, which may be a robotic arm of a robotic surgicalinstrument, having an elongated shaft and preferably an articulatable“wrist” or articulation joint located at its distal or working end.

The tool heads disclosed and described herein are particularly, but notexclusively, suited for use in cardiac ablation procedures for thetreatment of atrial fibrillation using electro-surgical RF energy, orsome other energy, as shown and described for example in U.S. Pat. No.6,546,935, which is incorporated herein by reference.

During the performance of cardiac ablation procedures, variousinstruments may be used to create transmural lines of ablation intissue, such as an ablation clamp having opposed jaw members havingopposed electrodes thereon, an ablation “pen” and a surgical dissector.Such instruments are shown generally in U.S. Pat. No. 7,113,831 and U.S.Published Application 2006/0084974 (showing an ablation clamp withopposed jaw members), U.S. Published Applications 2006/0161147 and2006/0161149 (both showing an ablation pen), and U.S. PublishedApplication 2005/0203561 (showing a lighted dissector), all of which areincorporated herein by reference. In another procedure, a clip may beapplied externally to the left atrial appendage (LAA) to reduce therisks of clot generation associated with the LAA. Such a clip and clipapplicator are shown in U.S. application Ser. No. 12/033,935, filed Feb.20, 2008, which is also incorporated herein by reference. Each of theaforementioned devices or tools is typically carried on its owndedicated hand piece and a shaft, with the operating head at the distalend thereof.

SUMMARY

By way of the present application, tools for performing cardiac ablationand other procedures are provided as discrete interchangeableindependent devices or tool heads that are intended to be used with acontrol arm, such as a robotic arm or a durable, e.gs, reusable, arm.The tool heads are provided with a tether connected directly thereto toprovide for actuation of the tool head. (As used herein, “actuation” or“actuable” are broadly understood to mean energizing or controlling thetool head mechanically, hydraulically, pneumatically, thermally, oractivating a light/laser/light pipe/fiber optic, or providing avacuum/suctionor fluid delivery and the like, as well as combinationsthereof,) Specifically, each of the tool heads may include at least onegripping or clamping surface designed to be carried by the jaws of aforceps or grasper mounted to the distal end of the shaft of the controlarm. The tool head may be removably mounted to the control arm in any ofa variety of ways described below, or by other mounting arrangements.

The actuation and/or energizing means for generating movement ispreferably connected to the tool head separate from the control arm in amanner that permits remote actuation/energization of the tool head,(i.e. external to the body) independent of the control arm after thetool heads have been introduced, for example, by minimally invasivemeans, to a surgical site interior of the body.

Because the tool head is completely independent from the control arms,the tool head may be passed from one control arm to another control arm,or exchanged between control arms, and the various tools may beselectively grasped by the control arm to permit instrument exchangesduring procedures. The tool heads may be introduced either through thesame access port as the control arm or through a separate access port,into the surgical site. Thus, in a procedure, all of the tool headsneeded for the procedure may be separately introduced into proximity ofthe surgical site, such as into a cavity at the start of the procedureand be readily available for use in connection with one or more controlarms.

In one embodiment, the tool heads are provided with an extending orfin-like surface for gripping by jaws of a control arm. Preferably, thefins are made of a material having some compressibility, which allowsthe jaws of control arm forceps to better grip and hold the tool head.

Additionally, or alternatively, the fin and the forceps may be formedwith complementarily-shaped interfitting surfaces that mate when thetool is gripped by the forceps. Such surfaces may be shaped to provideselected alignment of the tool with respect to the forceps. In oneembodiment, for example, the jaws of the forceps of the control arm havean open or relieved interior or apertures or fenestrations and thegripping surfaces of the tool heads may be formed with one or morecomplementarily-shaped protrusion that is received within thefenestration interior of the jaws.

In a further alternative, these surfaces may be reversed, and thegripping or clamping surface may comprise a pocket or aperture thatreceives the closed jaws or projecting surfaces thereof and may begrasped by moving the jaws toward their open position.

As another option, the tool heads may be formed with two or moregripping surfaces, which permits a tool head to be simultaneously heldby two or more control arms so that the tool head can be passed from afirst control arm to a second control arm, and allows for both controlarms to work in unison.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a control arm having an articulatablewrist and a grasper at its distal end.

FIG. 2 is a perspective view of the distal end of the control arm ofFIG. 1 and a tool head in the form of an ablation clamp in accordancewith the present disclosure.

FIG. 3 is a perspective view similar to FIG. 3 in which the tool head isheld by the control arm.

FIG. 4 is a cross-sectional view taken along line 4-4 of FIG. 3.

FIG. 5 is a perspective view of the distal end of the control arm ofFIG. 1 and a tool head in the form of a blunt dissector in accordancewith the present disclosure.

FIG. 6 is a perspective view similar to FIG. 5 in which the tool head isheld by the control arm.

FIG. 7 is a cross-sectional view taken along line 7-7 of FIG. 6.

FIG. 8 is a perspective view of the distal end of the control arm ofFIG. 1 and a tool head in the form of a clip applicator in accordancewith the present disclosure.

FIG. 9 is a perspective view similar to FIG. 8 in which the tool head isheld by the robotic arm.

FIG. 10 is a cross-sectional view taken along line 10-10 of FIG. 9.

FIG. 11 is a perspective view of the distal end of the control arm ofFIG. I and a tool head in the form of an ablation pen in accordance withthe present disclosure.

FIG. 12 is a perspective view similar to FIG. 11 in which the tool headis held by the control arm.

FIG. 13 is a cross-sectional view taken along line 13-13 of FIG. 12.

FIG. 14 is a perspective view similar to FIG. 11 except that it has analternative clamping surface.

FIG. 15 is a perspective view similar to FIG. 14 in which the tool headis held by the control arm.

FIG. 16 is a cross-sectional view taken along line 16-16 of FIG. 15.

DETAILED DESCRIPTION

With reference to FIG. 1, there is seen one form of a control arm withwhich the surgical instruments disclosed herein are adapted to be used.The illustrated control arm is a robotic arm 10 comprising a componentof a telesurgical system (not shown), such as the davinci SurgicalSystem, available from Intuitive Surgical, Inc. of Mountain View,Calif., shown in U.S. Pat. No. 6,770,081, which is incorporated hereinby reference. Alternatively, the control arm is not necessarily arobotic arm or associated with a robotic surgical system, although thatis one system in which this subject matter has particular application.For example, the control arm may simply be a standard surgical graspingtool such as those available from Fehling Surgical Instrument, Inc., ofAcworth, Ga., or graspers of the type disclosed in U.S. Pat. No.5,728,121, which is incorporated herein by reference.

The illustrated robotic arm 10 includes an elongated shaft 12 and awrist-like articulation mechanism 14 at its distal end, A housing 16 atthe proximal end of the assembly 10 couples the assembly to thetelesurgical system. The housing 16 contains the mechanism forcontrolling (e.g., rotating) the shaft 12, articulating the wrist 14,and actuating a forceps 18 mounted to the wrist mechanism 14 carried onthe distal end of the shaft 12. The illustrated forceps 18 is known as acardiere forceps in which the jaws 20 are fenestrated, or otherwise havean opening or relief in their gripping surface. Preferably, and asshown, the gripping surfaces of the jaws are serrated.

With reference to FIGS. 2-4, there is seen a tool head 22 comprising anclamp having opposed jaws 24, 26 for use with the robotic arm assembly10 shown in FIG. 1. The illustrated clamping jaws 24, 26 may preferablybe as shown and described in U.S. Pat. No. 7,113,831 and U.S. PublishedApplication 2006/0084974. Each jaw 24, 26 includes an elongatedelectrode (not shown) that is adapted to receive bipolar RF energy forcreating transmural ablation lines in tissue held between the jaws 24,26. Jaw 24 may be stationary, while jaw 26 may be moveable toward andaway from jaw 26, with the mating surfaces of the jaws 24, 26 remainingsubstantially parallel. The electrical and mechanical connections 28 foractivating the electrodes carried on the jaws and for opening andclosing the jaws are connected to the tool head 22 separate andindependent from the control arm, such as shaft 12 of the robotic tool10.

Because the activation sources for the tool head are separate from thecontrol arm, the tool head may be exchanged between different controlarms, the tool head may be released from the control arm and a differenttool head attached, and multiple tool heads may be preselected andplaced in or near the surgical site for user convenience. This featurehas particular benefit in a minimally invasive surgery in that, forexample, the tool heads expected to be needed for a selected surgery maybe inserted in to the body cavity, creating what may be referred to as atool kit or tool chest within the body cavity, and the surgeon orrobotic instrument may use a single control arm for grasping and usingeach tool head, as needed, without the need for repeatedly removing thecontrol to exchange or replace tools as needed. Further, the tool headsmay be for one-time use only and disposable, with the control arm, andany associated articulation control mechanism, being reusable, if sodesired.

To facilitate the grasping of the individual tool head 22 by the grasper18, the tool head 22 may be provided, in one embodiment, with a clampingsurface 30. Specifically, the illustrated clamp carries a generally flator fin-like protrusion on the side of the tool opposite the jaw members24, 26, although other configurations for the clamping surface or otherarrangements other than a clamping surface are also contemplated. Inorder to enhance the grip of the jaws on the clamping surface, the fin30 has opposed protrusions 32 sized and shaped to fit into thefenestrations 20a on the jaws 20 of the forceps 18. As shown, theprotrusions 32 are formed on both surfaces of the clamping surface,although a protrusion could be formed on only one of the clampingsurfaces. Also, if the fenestration 20a and protrusion 32 arecomplementarily shaped, such as one concave and the other convex, andnon-circular, gripping of the tool head 22 in a particular orientationto the jaws 20 is facilitated.

As noted above, it is contemplated that other tools or tool heads usefulin performing cardiac ablation or other intended procedures couldsimilarly be provided with a clamping or gripping surface or othergrasping arrangement. Turning to FIGS. 5-7, a tool head 34 in the formof a blunt dissector is shown in combination with the working end of acontrol arm such as a robotic shaft. The illustrated dissector 34 maypreferably be as shown and described in U.S. Published Application2005/0203561. The dissector comprises an arcuate section 36 with asmooth outer surface and a generally circular cross-sectional shape.However, the geometry may vary depending on the targeted anatomy. Thearcuate section 36 has a blunt and rounded distal end 38. Asillustrated, the distal end of the dissector 35 includes a light source40 that emits visible energy. The light source 40 is powered by abattery carried in housing 42 that is connected to the dissector 35 byan insulated conductor/tether 44 such that the battery remains externalto the body during a procedure. The battery housing 42 includes a switch46 for activating the light source 40. To facilitate the grasping of thedissector 34 by the jaws 20 of the forceps 18, the dissector 35 includesa clamping surface 48 at its proximal end having at least one andpreferably opposed posts 50 adapted to be received in the fenestrations20a of the opposed jaws 20.

FIGS. 8-10 show the working end of the robotic shaft in combination withtool head 52 comprising a clip applicator for applying an occlusionclamp or clip to the tissue to be closed, which may include the leftatrial appendage, or other vessel or tissue. The clip applicator andclip may be as shown and described in pending U.S. patent applicationSer. No. 12/033,935, filed Feb. 20, 2008. The tool head comprises aframe 54 with an open interior with a fabric covered clip 56 preloadedtherein. The clip 56 comprises two legs 58, 60 that are spread apart adistance sufficient to allow it to be placed over target tissue, e.g.,the left appendage of the heart. To this end control sutures, wires orstrings 62 are attached to leg 60 of the clip such that retraction ofthe sutures 62 spreads the legs 58, 60. The proximal end of the sutures62 remain external to the body for remote actuation. For cooperationwith a control arm, the clip applicator 52 includes a clamping surface64 with elongated protrusions 66 similar to that shown in conjunctionwith the ablation clamp 22 described above. In addition, the clipapplicator 52 is provided with a second clamping surface 68 similar toclamping surface 64 and having elongated protrusions 70. The secondclamping surface permits the tool head 52 to be grasped simultaneouslyby two robotic arm assemblies 10, thus permitting the tool head to bepassed from one robotic arm to a second robotic arm. This feature is notlimited to a clip applicator, and as such, each of the tool headsdescribed herein may also include a second clamping surface.

FIGS. 11-13 show an ablation pen 72 in combination with the distal endof the control arm of a robotic surgical instrument. The ablation pen 72may preferably be as shown and described in U.S. Published Applications2006/0161147 and 2006/0161149. The ablation pen 72 includes a head 74carrying two electrodes (not shown) capable of being energized withbi-polar RF energy. An insulated electrical conductor 76 is provided (asa tether) for transmitting energy to the electrodes.

Similar to the examples described above, the pen 72 is provided with aclamping surface 78 adapted to be held between the jaws 20 of theforceps 18. As seen in FIG. 11, the clamping surface 78 does not includethe complementarily-shaped protrusions associated with the clampingsurfaces of the previously disclosed embodiments. Instead, the clampingsurface 78 is made from or provided with a covering of a compressiblematerial that is more readily deformable under the closing forceachieved by the jaws 20, thus permitting the jaws 20 to more firmly gripthe clamping surface 78. This is shown in FIG. 13, where it can be seenthat the clamping surface 78 has been deformed such that a portion 80thereof resides in the fenestrations of the jaws 20. As can beappreciated, the clamping surface of the tool head may be bothdeformable and have complementarily-shaped protrusions to enhancegripping by a forceps. Other friction-enhancing materials or surfacesmay be used to enhance grasping by the control arm.

While each of the tool heads described thus far has had a clampingsurface adapted to be held between the closed jaws of a forceps, otherconfigurations for securing the tool head are contemplated. For example,and with reference to FIGS. 14-16, the tool head 72 (shown forillustrative purposes in the form of an ablation pen as in FIGS. 11-13)is provided by a receptacle 84, which may also be referred to as aclamping surface, that is adapted to be held by the spread-apart or openjaws of the forceps. Specifically, the clamping surface 84 is in theform of a pocket or sleeve with an open interior sized to receive theclosed jaws 20 of the forceps 8. The pocket or sleeve 84 has opposedside walls 86 that are engaged by the outer surface of the jaws 20 (bestseen in FIG. 16). Of course, as described in connection with the outerembodiments, the interior of the sleeve may be provided with protrusionssized to be received in the fenestrations of the jaws and/or adeformable or enhanced friction surface.

While the surgical instruments have been described in terms of thoseparticularly appropriate for cardiac applications, this is not by way oflimitation, but for illustration. Indeed, any surgical instrumentsadapted for use with robotic devices may advantageously include theclamping surface described above.

1. A surgical instrument comprising: an elongated shaft having aproximal end and a distal end; a separate tool head for performing aprocedure on a target tissue, the tool head being remotely actuable, anda tool head engagement member carried at the distal end of the shaft,the engagement member being remotely actuable to engage and release thetool head.
 2. The surgical instrument of claim 1 in which the engagementmember comprises opposed jaws.
 3. The surgical instrument of claim 1 inwhich the engagement member and tool head include complementarily shapedengageable surfaces.
 4. The surgical instrument of claim 2 wherein atleast one of the opposed jaws has a grasping surface with one of aprotrusion or a relieved area thereon and the tool head includes aclamping surface with the other of the protrusion or relieved surfacethereon, the surfaces cooperating to enhance engagement between the toolhead and the engagement member.
 5. The surgical instrument of claim 1wherein the tool head includes a clamping surface that is compressible.6. The surgical instrument of claim 1 wherein the tool head has firstand second spaced apart clamping surfaces adapted to be engaged by anengagement member.
 7. The surgical instrument of claim 2 furthercomprising a clamping surface on the tool head adapted to be heldbetween the jaws of the engagement member.
 8. The surgical instrument ofclaim 2 further comprising a clamping surface on the tool head andwherein the clamping surface is adapted to be held by open jaws.
 9. Thesurgical instrument of claim 1 further comprising a tether operativelyassociated with the tool head and extending therefrom separate from thecontrol arm for actuating the tool head.
 10. A tool head for performinga medical procedure for use in combination with a surgical device havinga shaft and a pair of jaws on the distal end of the shaft, the tool headcomprising a clamping surface for engagement by the jaws of the forcepsand a tether extending from the head and separate from the surgicaldevice for actuating the tool head.
 11. The tool head of claim 10wherein the clamping surface has at least one of a protrusion orrelieved area shaped to engage the other of a protrusion or a relievedarea on at least one of the jaws.
 12. The tool head of claim 11 whereinthe clamping surface has opposed protrusions or relieved areas shaped toengage complementary protrusions or relieved areas of the jaws.
 13. Thetool head of claim 10 wherein the clamping surface is compressible. 14.The tool head of claim 10 wherein the tool head has a second clampingsurface extending therefrom adapted to be held by the jaws.
 15. The toolhead of claim 10 wherein the clamping surface is adapted to be held byopen jaws.
 16. The tool head of claim 10 wherein the clamping surface isadapted to be held between the jaws.
 17. A method for performing amedical procedure in a surgical field comprising: creating access to thesurgical field; introducing into the surgical field at least first andsecond remotely actuable toot heads for performing various aspects ofthe medical procedure; introducing into the surgical field a firstcontrol arm having a distal end with a tool head engagement memberassociated therewith; engaging the first tool head with the tool headengagement member of the first control arm; positioning the first toolhead and remotely actuating the tool head to perform a step of medicalprocedure; releasing the first tool head from the tool head engagementmember of the first control arm; engaging the second tool head with thetool head engagement member of the first control arm without removingthe engagement member from the surgical field; and positioning thesecond tool head and remotely actuating the second tool head to performa step of the medical procedure.
 18. The method of claim 17 furthercomprising: introducing into the surgical field a second control armcomprising a distal end with a tool head engagement member associatedtherewith; simultaneously engaging a selected one of the first andsecond tool heads with the tool head engagement members of both controlarms; and releasing the selected tool head from the first control arm.19. The method of claim 17 wherein the surgical field comprises a bodycavity and the tool heads and control arm are introduced into the bodycavity through an access port.
 20. The method of claim 17 wherein thetool head engagement member has a surface shape complementary to aclamping surface on the tool heads.
 21. The method of claim 17 whereinthe tool heads are adapted to perform cardiac ablation procedures. 22.The method of claim 17 wherein the tool heads are selected from thegroup consisting of an RF ablation clamp, an RF ablation pen, a bluntdissector and a clip applicator.
 23. A surgical instrument comprising atool head; a tether attached to the tool head for actuating the toolhead, and at least one engagement surface adapted to interface with aseparate control arm.
 24. The surgical instrument of claim 23 whereinthe tool head is selected from the group consisting of an RF ablationclamp, an RF ablation pen, a blunt dissector and a clip applicator.